Cracks in the Ice: Why a 'frozen' distribution Linux kernel isn't the safest choice for security:

https://ciq.com/blog/why-a-frozen-linux-kernel-isnt-the-safe...

This is an executive summary of research that my colleagues Ronnie Sahlberg and Jonathan Maple did, published as a whitepaper with all the numeric details here:

https://ciq.com/whitepaper/vendor-kernels-bugs-stability/